/* let str = 'a\nb c\td';
let regexp = /\S/g;
let result = regexp.exec(str);
console.log(result);
result = regexp.exec(str);
console.log(result);
result = regexp.exec(str);
console.log(result);
result = regexp.exec(str);
console.log(result);

let regexp2 = /[\s\S]/;

 */
let regexp3 = /a\.b/;
let str3 = 'a.b';
let result = regexp3.exec(str3);
console.log(result);

let regexp4 = /^aaa$/;